Concrete work in Altadena
Altadena sits directly north of Pasadena at about 1,358 feet, climbing toward the San Gabriel Mountains. It counted 42,846 residents in 2020 across 8.48 square miles, and it has no city government: Los Angeles County runs its permits and roads. Before the fire, the county's own profile showed about 90 percent of homes built before 1979 and about 90 percent single-family. Christmas Tree Lane, the row of giant deodars on Santa Rosa Avenue, still runs from Woodbury Road to Altadena Drive.
The Eaton Fire and Altadena's rebuild
The Eaton Fire started on January 7, 2025, at 6:18 p.m. and was contained on January 31. By the county's count it burned 14,021 acres, destroyed 9,414 structures, damaged 1,074 more and killed 19 people. A county Board of Supervisors letter puts the damage or destruction of 6,921 of those structures in unincorporated Altadena and Kinneloa Mesa. For concrete, that means foundations, driveways, walks and walls on thousands of lots at once.
| Rule | What the county says | Concrete angle |
|---|---|---|
| Like-for-like | Up to 10% or 200 sq ft larger, whichever is greater | A slightly larger foundation can still qualify |
| Debris first | Debris removal must be done before a building permit | The new slab is planned for a cleared lot |
| Soils report | Not needed for a conventional raised or slab-on-grade foundation with continuous footings | Saves $600 to $1,500 on many lots |
| Fees | Not collected from owner-occupants living there on or before Jan 7, 2025 | Rentals and LLC-owned homes pay |
| Walls and fences | Must comply with Title 22 requirements | Rebuilt retaining walls follow current zoning |
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From LA County's recovery FAQ, fee deferral page and rebuild ordinance, read October 2026. The interim rebuild ordinance was extended a second time on July 28, 2026; check the current end date with the county.
The Altadena One-Stop Permit Center
The county's Altadena Building and Safety Office, 464 W. Woodbury Road, Suite 210, doubles as the One-Stop Permit Center for fire rebuilds. It is open weekdays from 8:00 to 4:30, with the last call for permits at 3:00, and intake is at 626-424-6743. A rebuilt concrete foundation is planned around that permit; an ADU foundation follows its own plans.
Driveways and walls at the county road
The street side of an Altadena lot belongs to the county. A driveway approach or curb cut needs a road construction permit, applied for through EPIC-LA. The county's rebuild guidance for the right-of-way adds specifics: a street plan is needed for a new or widened driveway or for curb and parkway drains, residential driveways are built with 4 inches of concrete over 6 inches of crushed aggregate base, and approaches follow standard plan SPPWC 110-2, Type B. It also notes that many Altadena streets have no curb, gutter or sidewalk at all.
What the county exempts
The county's exempt-work list skips a building permit for retaining walls that retain no more than 4 feet from the bottom of the footing to the top of the wall, unless they support a surcharge, and for decks, walks and driveways no more than 30 inches above grade. Digging stays out of a grading permit up to 50 cubic yards and less than 2 feet deep. Parkway trees are a separate matter: trimming, removing or harming a county parkway tree without a permit is unlawful.
Altadena's community standards and stormwater
Altadena's Community Standards District adds local zoning on top of the county code. Its checklist, revised October 20, 2025, sets a 20-foot front yard for all disaster recovery rebuilds, caps walls and fences at 3 1/2 feet within the driveway zone and 6 feet outside it, and lists 10 feet of driveway access for one or two units. On runoff, the county's residential Low Impact Development rules apply when new work or a remodel alters 50 percent or more of a lot's impervious surfaces; such projects use at least two LID measures, and one option is making at least half the pavement on the lot porous. The stormwater guide explains the options.
Concrete prices for Altadena
constructlytools' Los Angeles guide (updated May 19, 2026) names Altadena among its moderate-slope areas, at $10 to $15 per square foot for reinforced driveways and patios, against $8 to $12 on flat lots. House foundations run $15 to $25 per square foot with Seismic Zone 4 detailing included, and a pump truck adds $500 to $900 where a truck can't reach. The soil and geology guide covers the ground at the foot of the San Gabriels.
